Ultrahigh-definition experimental camera system with an 8M-pixel CCD

Abstract

An ultra-high defmition experimental camera system has been designed with double the horizontal and vertical resolution ofHDTV. An 8Mpixe1 CCD with a progressive 60 frame-per-second scan-rate has been developed for the system. The 34 mm x 17.2 mm image area has 4046(H) x 2048(V) active imaging pixels with 8.4m squares. This CCD has a split-frame transfer stmcture and sixteen 37. 125 MHz outputs so that the vertical and horizontal transfer frequencies are almost the same as those of HDTV. The split$rame transfer stmcture halves the required VCCD clock speeds and thus improves charge transfer efficiency. The multiple-output structure with its 16 outputs enables high datarate imaging for ultra-high resolution moving pictures. In the signal processing section, analog gain adjustment circuits correct for the mismatches in the characteristics of outputs, and a correlated double-sampling technology is employed on each of the 16 CCD output signals. The output signals are digitized by 12-bit ADCs. The converted signals are then sent to the digital signal processing (DSP) circuits. In the DSP circuits, the upper half ofthe captured image is vertically inverted. All of the output data is then merged into a 4K x 2K pixel image and reformatted to create twenty-four 640(H) x 480(V) pixel sub-images for image processing. After contour compensation processing, the video signals are converted into an analog signal and presented on two ultra high resolution video monitors.